This invention relates to electrical connections or splices for wire wound resistors of the type comprising a cylindrical core of insulating material and a resistance wire wound helically over the core. A commonly used type of splice connection is disclosed in U.S. Pat. No. 2,748,456 and a machine for applying these slices to resistors is shown in U.S. Pat. No. 2,673,345.
The splicing device shown in the above identified U.S. Pat. No. 2,748,456, is widely used and has proved to be widely successful however, under some circumstances there is a requirement for a splicing device having improved characteristics in certain aspects. The prior art splicing device referred to above comprises a simple sheet metal U-shaped member which is crimped onto the wire wound resistor so that the internal surfaces of the connecting device contacts the helically wound wire on the resistor core. The lead wire is positioned on the surface of the resistor with its axis extending parallel to the axis of the resistor. After crimping, the lead wire is gripped between the edges of the sidewalls in the crimped connecting device. The edges of the connecting device thus contact the lead wire and the internal surface of the contacting device contacts the resistance wire on the resistor.
In accordance with the principles of the instant invention, a U-shaped connecting device is provided which has a semi-cylindrical depression in its web which conforms to, and receives, the lead wire. The sidewalls are reversely folded at their outer ends to provide an inner layer or thickness of metal in each sidewall. The inner layer extends along the internal surface of the outer layer towards the web. The ends of the inner layers are swaged to facilitate electrical contact with the lead wire. When the connecting device is crimped onto the resistor, the sidewalls are folded into surrounding and embracing relationship with the resistor core and the inner layers are displaced towards the web relative to the outer layers. The ends of the inner layers are thus moved against the lead wire to establish contact therewith.
It is accordingly an object of the invention to provide an improved splicing device for wire wound resistors. A further object is to provide a crimped connection between a wire wound resistor and a lead wire having improved electrical and mechanical connections between the lead wire and the connecting device.